Can Tomatoes Protect Your Health?

You may have read articles urging you to eat lots of tomatoes to protect your health. But is it true? Are tomatoes really a superfood? The answer is … maybe!

Many studies have found a link between eating lycopene, a compound in tomatoes, and a lower risk of cancer, heart disease, and stroke. Researchers are beginning to study whether lycopene also can help with other issues, such as bone health.

What is lycopene?

Lycopene is what gives tomatoes their red-orange color. And it’s not just tomatoes: Watermelon, pink grapefruit, and other similarly colored fruits and vegetables also contain lycopene.

There are several ways that lycopene is thought to be good for you. Lycopene can work as an antioxidant to decrease damage to your cells from free radicals. Your cells, as part of their normal behavior, create unstable molecules called free radicals. These free radicals can damage normal cells. Over time, built-up cell damage may lead to cancer and other diseases. Antioxidants protect your cells by counteracting these free radicals. Scientists have found lycopene to be one of the most effective antioxidants when it comes to protecting cells.

Lycopene also helps protect you against disease by reducing inflammation in the body. In the February 18, 2015 Think Pink, Live Green column, I talked about short-term inflammation, which can be an important part of the healing process. But long-term inflammation can wear down your cells and lead to genetic changes in your cell’s DNA. DNA, or deoxyribonucleic acid, is a substance in your cells that tells them what to do. Inflammation also can cause mistakes in these instructions. So cells might get the wrong directions and start to grow out of control. Over time, if the cells keep growing in an uncontrolled way, they can develop into a cancer. Research suggests that lypocene can help reduce inflammation in the body, which may mean lower cancer rates.

Some research also hints that lycopene may help protect healthy cells from the side effects of radiation treatment by blocking the free radicals that radiation may produce in cells.

What does the research say?

Proving the benefits of lycopene is difficult. First, it’s hard to figure out exactly how much people are eating. That’s because lycopene content in each food varies and the amount of these foods we each eat is tough to remember and track. So two people who each ate a medium tomato may have eaten different amounts of lycopene.

Measuring the amount of lycopene in a person’s blood is more accurate.

Studies using blood levels of lycopene showed a stronger link to lower breast cancer risk than studies that just used diet questionnaires.

A large analysis of more than a half-million people found that eating lycopene daily is associated with a lower risk of prostate cancer. Other studies have suggested that lycopene also may be linked with a lower the risk of head and neck, lung, and stomach cancers. But more research needs to be done to confirm these benefits.

Given all the potential health benefits of lycopene, you’re probably asking, “How do I pick foods that contain lycopene?”

How to get more lycopene into your diet

In general, red, orange, and yellow fruits and vegetables tend to have lycopene: apricots, pink grapefruit, pink guava, papaya, red carrots, and watermelon. But not all red-colored produce contains lycopene. For example, strawberries and cherries don’t have it.

Tomatoes have the highest lycopene content of any food, followed by watermelon. Color matters — the lycopene in the fruit increases dramatically as it ripens and the color gets more vivid.

Processed tomato foods such as canned or jarred tomato paste, marinara sauce, catsup/ketchup, and salsa usually have more lycopene than fresh tomatoes. That’s because heating tomatoes to turn them into food products makes it easier for your stomach to release the lycopene and absorb it into your body. However, you should limit the amount of catsup/ketchup you eat because it contains a LOT of sugar.

The Harvard Health Blog measured the amount of lycopene in some common foods, so you can see which foods give you the most bang for your lycopene buck, so to speak.

Food

Micrograms of lycopene

½ cup canned tomato puree

27,192

1 cup canned tomato juice

21,960

1 wedge of raw watermelon

12,962

½ cup ready-to-serve marinara sauce

6,686

1 tablespoon canned tomato paste

3,140

1 tablespoon catsup/ketchup

2,506

½ pink or red grapefruit

1,745

1 tablespoon salsa

1,682

One sun-dried tomato

918

One slice of raw tomato

515

One cherry tomato

437

(Godman, 2012)

If you like exact measurements, get ready to do some math! To get the number of milligrams, which is a more familiar measurement than micrograms, you’ll need to divide micrograms by 1,000. So the 27,192 micrograms in one-half cup of canned tomato puree is equal to about 27 milligrams. It’s important to note that some cans are lined with a resin containing bisphenol A (BPA), which may carry health risks, as I discussed in a previous column. Look for glass-bottled alternatives, where possible, or cans that are labeled BPA-free.

There’s no official recommendation for how much lycopene a person should eat per day. Still, Dr. Edward Giovannucci, an expert on nutrition and cancer at Harvard University, recommends at least 10,000 micrograms (10 milligrams) a day from food.

It’s also good to know that eating lycopene with oil or fat helps the body absorb it better. You can try making tomato sauce for pasta with some olive oil, or adding olives to your pasta sauce or salsa.

But what if you really don’t like tomatoes? Could a lycopene pill be a substitute? Scientists haven’t studied that much, so we don’t really know. We do know that there’s no evidence that taking supplements is as good for you as eating the whole fruits, vegetables, beans, and grains that contain the compound in the supplement. Most experts strongly believe that it’s the combination of these compounds and other helpful ingredients in the same food and in the other foods you eat that keeps your body healthy. So skip the pill form of these plant compounds. It’s most beneficial to eat a balanced diet with a variety of foods that includes five or more cups of fruits and vegetables per day and food from other plant sources, such as whole-grain breads, cereals, nuts, seeds, rice and pasta, and beans.

Do you have a favorite tomato recipe? Mine is a delicious tomato soup that my mom taught me how to make. Share yours in the comments below.

If you’re interested in growing your own tomatoes, check out Tomatoes: A Growing Guide from Rodale’s Organic Life. It contains lots of tips and tricks to get the best-tasting tomatoes.

Marisa Weiss, M.D. is the founder, president, and chief medical officer of Breastcancer.org, the world's most trafficked online resource for medically reviewed breast health and breast cancer information, reaching over 14 million visitors per year. A breast cancer oncologist with over twenty years of active practice in the Philadelphia region, Dr. Weiss is regarded as a visionary advocate for her innovative and steadfast approach to informing, empowering, and treating patients with breast cancer.